Learn FORTRAN with Real Code Examples

Fortran excels at high-performance numerical computation and array processing.

It supports modular programming, procedures, and modern object-oriented features in newer standards.

Commonly used in scientific simulations, weather modeling, computational physics, and engineering calculations.

Modules and subroutines

Array operations and intrinsic functions

Derived data types

Control structures (loops, conditionals)

I/O facilities for formatted/unformatted data

Variables, constants, and types

Control structures (if, do, select case)

Subroutines and functions

Modules and derived types

Arrays and intrinsic operations

source.f90 files

modules/

libraries/

tests/

executables/

Write .f90 or .f95 source file

Compile with Fortran compiler

Link libraries if needed

Run executable

Debug using gdb or compiler flags

Beginner: simple arithmetic & loops

Intermediate: subroutines and modules

Advanced: parallel programming & large-scale simulations

Expert: HPC code optimization, legacy code maintenance

Faster than interpreted languages for numeric computation

Better array handling than C in some cases

Less general-purpose than Python or Java

Strong legacy presence in HPC vs newer languages

Syntax can be verbose compared to modern languages

1957 – Fortran I released

1960 – Fortran II

1978 – Fortran 77 standard

1990 – Fortran 90 (modern features)

2003–2025 – Fortran 2003, 2008, 2018 standards for OOP and parallelism

Module: container for functions/subroutines

Subroutine: procedure with no return value

Function: procedure returning value

Intrinsic function: built-in Fortran function

Array: collection of same-type elements